Hydraulic operator and circuit therefor

ABSTRACT

Disclosed is a hydraulic operator for an automatic door having a hydraulic circuit in which the inlet and discharge lines from the power cylinder are interconnected by a spring-biased operator for a oneway valve disposed in one of the parallel paths of the discharge line. Pressure in the inlet line prevents the seating of the valve to allow unimpeded flow through the discharge line during normal powered operation. Absence of pressure in the inlet line, as under manual operation when power is shut off, allows the valve to seat and discharge flows through a parallel path which is restricted to provide for the controlled manual opening of the door as well as the controlled opening and closing of the door during emergency manual door operation in the opposite from normal direction. Also disclosed is a checking piston design in which the checking piston has an annular clearance with the supporting piston rod for self-alignment with the checking chamber to accommodate misalignment between the checking chamber and the piston rod. Resilient O-rings in the end wall of the checking piston frictionally engage a mating wall to hold the checking piston in its laterally adjusted position.

[451 Feb, 19, 11974 [541 HYDRAIUMC lPlERATR AND ClRCUll'l THEREFR [75] Inventors: Harold W. Ferguson, New Hartford; Paul C. Schultheiss, Bristol, both of Conn.

[73] Assignee: The Stanley Works, New Britain,

Conn.

[22] Filed: May 1141, 1973 [21] Appl. No.: 359,914

Related US. Application Data [63] Continuation of Ser. No. 94,479, Dec. 2, 1970,

abandoned.

[52] US. Cl 911/420, 91/394, 49/139 [51] int. Cl...ll"15h 1li/08, F15b 13/04, F15b 15/22 [58] Field ot Search... 49/139; 91/420, 396, 26, 394

[56] Reterences Cited UNITED STATES PATENTS 1,023,267 4/1912 Gerber et al 49/139 2,483,312 9/1949 Clay 91/420 2,517,l64 8/1950 Arps 91/420 2,927,429 3/196() Carlson 49/139 3,145,734 8/1964 Lee et al..... 91/420 3,164,959 1/1965 Gondek 91/420 3,266,381 8/1966 Rohde 91/420 3,303,746 2/1967 Schmoeger 91/26 Primary Examiner-Paul E. Maslousky Attorney, Agent, or Frm-Prutzman, Hayes, lalb t Chilton [5 7] ABSTRACT Disclosed is a hydraulic operator for an automatic door having a hydraulic circuit in which the inlet and discharge lines from the power cylinder are intercom nected by a spring-biased operator for a Oneway valve disposed in one of the parallel paths of the discharge line. Pressure in the inlet line prevents the seating of the valve to allow unimpeded tlow through the discharge line during normal powered operation. Absence of pressure in the inlet line, as under manual operation when power is shut off, allows the valve to seat and discharge flows through a parallel path which is restricted to provide for the controlled manual opening ofthe door as well as the controlled opening and closing of the door during emergency manual door operation in the opposite from normal direction. Also disclosed is a checking piston design in which the checking piston has an annular clearance with the supporting piston rod for self-alignment with the checking chamber to accommodate misalignment between the checking chamber and the piston rod. Resilient O- rings in the end wall of the checking piston frictionally engage a mating wall to hold the checking piston in its laterally adjusted position.

11 Claim, d Drawing Figures PAIENIEU ri 1 91974 snm 1 of 3 N ...El

lHuVEIWVORs HAROLD w. FERGUSON PAUL QSCHULTHEISS pg/Mw, MM@ BY I [www TGRNEYS HYDRAULIC OPERATOR AND CIRCUIT THEREFOR This is a continuation, of application Ser. No. 94,479, filed Dec. 2, 1970, now abandoned.

This invention relates to power operators for automatic doors and more particularly to the hydraulic operator therefor.

Itis an object of this invention to provide a hydraulic door operator having a unique hydraulic circuit for controlled door opening and closing operation under manual, automatic, and emergency breakout in the reverse direction of opening.

Another object of this invention is to provide an improved hydraulic operator which is provided with selfadjusting checking pistons.

Other objects will be in part obvious and in part pointed out more in detail hereinafter.

The invention accordingly consists in the features of construction, combination of elements and arrangement of parts which will be exemplified in the construction hereafter set forth.

In the drawings:

FIG. 1 is a top view, partially broken away, of a door operator embodying this invention;

FIG. 2 is a side view of a doorway, partially broken away, showing the in-header mounting of the operator of FIG. 1;

FIG. 3 is a schematic hydraulic circuit of the operator; and

FIG. 4 is a side view, partially broken away of the power cylinder of the operator.

Referring now to the drawings, in which like numbers refer to like parts throughout the several views, FIGS. 1 and 2 show a preferred embodiment of the door operator of this invention comprising a spindle subassem bly 10, a power cylinder subassembly 12, a double acting closing spring subassembly 14, a solenoid actuated control valve subassembly 16, a pump-accumulatorreservoir subassembly 18, a pump motor 20 a control box 22, and a mode selector switch 23.

As shown in FIG. 2, the self-contained operator is mounted by the header 44 ofa doorway between a pair of supporting jambs 24 by a pair of mounting brackets 26 secured to the jambs 24 by a plurality of screws 28.

The spindle subassembly is provided with a noncircular drive spindle 36 which is shown as being engaged in a complementary recess in the top edge of the door 37 to serve as a door pivot and to provide a driving connection with the door.

As shown in FIG. 2, each ofthe subassemblies 10-22 are individually mounted on the supporting plate 30 by a plurality of fasteners 40 with a plurality of longitudi nally disposed nipples 42 interconnecting the pumpaccumulator-reservoir assembly 18, the valve assembly 16. and the power cylinder l2 to provide hydraulic connections automatically upon the relative longitudinal movement of these members during assembly. Each nipple 42 is provided with an O-ring adjacent each of its ends and, when received in the aligned recesses of the adjacent components of the door operator during assembly on the mounting plate 30, automatically provide leakproof hydraulic connections therebetween.

FIG. 3 is a schematic showing of the unique hydraulic circuit incorporated in the design. The motor is connected to the pump-accumulator-reservoir assembly 18 (FIGS. l and 2) which includes the positive displacement pump 50, the accumulator 52, the reservoir 54 and the one-way valve S6. The power supplied to the motor 20 is controlled by a switch 58. The accumulator 52 is provided with a movable wall 60 to divide the interior thereof into a gas chamber 62 and a liquid chamber 64, and the switch 58 is connected to energize the motor 20 when the fluid is discharged from the liquid chamber 64 of the accumulator and to deenergize the motor when the accumulator is recharged to a preset level at the end of a power stroke. The oneway valve 56 prevents the reverse flow of hydraulic fluid when the motor 20 is de-energized.

The hydraulic control system includes a three-way valve assembly 66 which is energized by a solenoid 68 against the bias of a helical return spring 70 to move valve 76 to the left to pass pressurized fluid from the accumulator 52 into the conduit 72 at a rate established by the adjustable opening speed control valve 73 in supply conduit 7l to power the piston 74 of the power cylinder 12 by moving the piston to the right as viewed in FIG. 3 to effect the power opening of the door through the rotation of the drive spindle 36.

After the traffic passes through the doorway, the solenoid 68 is de-energized and the spring 70 returns the valve 76 to its right-hand position, as viewed in FIG. 4, to seal the connection between the accumulators 52 and the conduit 72. Discharge conduit 78 from the valve 66 is then connected to conduit 72 so that the pressurized fluid may f1ow past the adjustable closing speed control valve 80 to return to the reservoir 54 under the power stored in the double acting spring assembly 14 during the opening movement of the door.

FIG. 4 discloses the details of the unique power cylinder 12. The cylinder includes a power piston 74 having a piston rod 134 which is connected by a clevis 144 and a pin 136 to a drive link 138 which in turn is connected to the spindle 36 through the drive plate 140 fixed thereto (FIG. l).

Since the drive link 138 is connected to the drive plate 140 and it angular relationship to the axis of the piston rod 134 is changed with changes in the axial position of the drive rod 134 (see FIG. 1), means are provided for giving full lateral support of the piston rod 134 against lateral forces thereon while accommodating the relative pivotal movement of the drive link 138 with respect thereto. As shown in FIG. 4, the power cylinder has an end extension 142 which engages the bearing surface of clevis 144 on the end of the rod 134 throughout its travel. The sidewall of the end extension 142 is provided with an axially extending slot 146 through which the drive linkage 1.38 may pass as the drive link 138 enters the end extension 142 so as to accommodate its relative angular position with respect to the piston rod 134.

The power cylinder 12 is provided with opening and closing checking pistons 168 and 194.

Another feature of this invention is that the opening checking piston 168 and the closing checking piston 194 are radially spaced from the piston rod 134 so as to be floatingly mounted thereon. The opening checking piston 168 engages an abutment 208 on the piston rod 134 to fix its axial position. The opening check piston 168, the power piston 74, a spacer sleeve 210 and the closing check piston 194 are axially assembled over the reduced end portion of the piston rod 134 and secured thereon by an annular washer 216 and a threaded fastener 218 received in the end of the piston rod. The checking pistons 168 and 194 are spaced from the reduced end portion of the piston rod 134 to provide annular clearances 214 therebetween so as to be radially free floating thereon. The checking pistons 168 and 194 are respectively provided with annular grooves 204 and 206 to receive O-rings. By virtue of the axial biasing force of O-ring 204 and 206, the checking pistons 168 and 194 are frictionally held in a radial position relative to piston rod 134 and are automatically aligned with checking chambers 160 and 148 respectively during the first operating cycle of the power cylinder 12. Moreover, this construction automatically accommodates and misalignment between the axis of the end extension 142 and the checking chambers 160 and 148 as well as for any distortion in the linearity of the piston rod 134 to prevent any binding which might occur due to any such inaccuracy or misalignment.

Referring to FIG. 4, the door operator functions as follows.

With the door closed and accumulator 52 charged to its operating level, the solenoid 68 may be energized in any suitable manner, as by an automatic carpet switch, a photoelectric cell, etc. (not shown) to power door spindle 36 and open the door 37 in its normal direction (counterclockwise as viewed in FIG. 3). The energization of the solenoid 68 shifts the valve 76 to provide communication between the accumulator 52 and the inlet conduit 72 to power cylinder 12 through conduit 71. The adjustable restriction 73 sets the rate of flow for the desired door opening speed.

Since the piston rod 134 is positioned with the closing checking piston 194 located as indicated by the dash lines of FIG. 4, the pressurized fluid passes from the conduit 72 (FIG. 3) to the end ofthe checking chamber 148 and through passageway 150 past oneway valve 152 into the power piston chamber end 156 to engage the end of the power piston 74 to provide a high starting force. As the piston 74 moves to the right during the opening stroke, as viewed in FIG. 4, the unpressurized fluid in power piston chamber end 158 on the opposite side of the piston 74 is discharged from the checking chamber 160 through conduits 162, 164 and 166 to the reservoir 54.

Toward the end of the power stroke, the opening checking piston 168 enters the checking chamber 160 to initially throttle the direct passage of fluid into checking chamber 160 from power piston chamber end 148 and then to trap the fluid remaining in the power piston chamber end 158 (FIG. 4). The trapped fluid is prevented from returning to the reservoir 54 through passage 172 by one-way valve 170 and must pass through the passage 174 past adjustable opening check valve 176 to be discharged to the reservoir 54 via the conduit 162 so that adjustable check valve 176 to provides a control for the deceleration of the door.

As the power cylinder 12 opens the door 37, the drive link 178 which is pivotally connected to the drive plate 140 of the door spindle and to the end of the spring plunger 182 moves the plunger 182 to the left to store energy in the spring subassembly 14 until the door 37 is in the desired door open position.

The door is held in its open position so long as the solenoid 68 is energized to maintain the door in its full open position due to the hydraulic pressure biasing the power piston 74 to the right.

When the solenoid 68 is de-energized, the helical spring returns the valve 76 to the left to disconnect the pressurized fluid in the accumulator 52 from the power cylinder 12 and to connect the closing checking chamber 148 to the reservoir 54 through conduits 72 and 78.

The energy stored in the spring subassembly 14 biases the door to its closed position through the plunger 182, drive link 178 and drive plate 140 of the spindle assembly.

The door closing speed may be regulated by adjustable restriction in the passage 78 which maintains the pressure in the pwoer piston chamber end 156 at an intermediate level to oppose the closing force of the spring.

As the power piston 74 approaches the closed position shown in dashed lines in FIG. 4, the closing checking piston 194 enters the closing checking chamber 148 and because of a peripheral clearance therewith initially throttles the passage of fluid between power piston chamber end 156 and the checking chamber 148 and then shuts off direct communication between these chambers. Since the check valve 152 prevents the flow of fuel from the power piston chamber end 156 through the passage 150 at this time, the trapped hydraulic fluid in the chamber end 156 is discharged through passage 196 past adjustable restriction 198 to decelerate the door to its final closing speed as the fluid is returned to reservoir 54 through the conduits 72 and 78.

The unique hydraulic circuit of this invention also provides for the regulation and control of the door operation when the door is manually opened in its normal direction as when the control switch 23 is set so that the solenoid 68 is not energized.

The power piston chamber ends 156 and 158 of the power cylinder l2 are maintained full at all times since the power cylinder l2 is disposed below the level of the hydraulic fluid in the reservoir 54 (see FIG. 2).

When the solenoid 68 is de-energized, atmospheric pressure is present in conduit 72 so that the spring biased piston 222 is biased to its upper position (FIG. 3). This allows the ball valve 224 to be seated against the seat 226 by the hydraulic fluid discharged from the power piston chamber end 158 as the power piston 74 begins to move to the right as the door is pushed open. A conduit 228 bypasses the check valve 224 and includes an adjustable restriction or orifice 230 which develops a pressure drop thereacross which varies inversely with the speed of manual movement of power piston 74 and regulates the dumping of fluid from chamber end 158 to reservoir 54. Hence the pressure within the chamber end 158 of power cylinder 12 limits the rate of door opening movement for the safety of a person in the path of the opening door under manual operation.

Energy is stored in spring subassembly 14 as the door is opened, and when the manual force on the door is released, the door is returned to its closed position at a controlled rate in the same manner as heretofore described in connection with the automatic operation of the door.

It will be apparent from FIG. 3 that during any closing of the door, gravity will cause hydraulic fluid to pass from the reservoir 54 through conduits 166 and 164 into the chamber end 158 of the power cylinder past the one-way valve 170 which is readily unseated by the suction force of the piston 74 during closing. lt is also apparent that during the manual opening of the door, the fluid will enter chamber end 156 of the power cylinder 12 from the reservoir 54 through conduits 166, 72, 150 and 154 with the check valves 220 and 152 being unseated by the suction pressure provided by the piston 74 when the closing checking piston 194 prevents direct communication between chamber end 156 and closing checking chamber 148 bypassing restriction 198 so that the rate of manual opening is regulated by restriction 230.

The operator of this invention further provides for the manual emergency opening of the door in the opposite from normal direction as, for example, might occur during power failure. In such operation, the spindle 36 and the drive plate 140 are rotated in the clockwise direction as viewed in FIGS. 1 and 3. The connection between the drive link 138 and the drive plate 14() is such with respect to the pivots 136 and 137 of the drive link 138 that drive link 138 reaches an overcenter position with respect to the axis of rotation of the spindle 36 when the door is opened in an emergency position a predetermined amount of the door opening movement. Prior to this, the piston 74 moves in the same direction (i.e., to the left as viewed in FIG. 4) as in closing following door opening in the normal (or counterclockwise) direction so that the closing checking piston 194 moves further into the closing checking chamber 148. Since the closing checking piston 194 cuts off direct communication for the discharge of fluid trapped in the power piston chamber end 156, the trapped fluid must flow through the conduit 196 (FIG. 3) where the restriction 198 limits the opening speed during the initial portion of the emergency opening of the door in the reverse direction, The sleeve 210 spaces the closing checking piston 194 a greater distance from the power piston 74 to provide an added amount of trapped fluid in the chamber end 156 of the power cylinder 12 for controlling the speed during the initial portion of the reverse opening movement of the door.

When the drive link 138 reaches the overcenter position with respect to its pivots and the center of rotation of the drive spindle 36, the power piston 74 begins to move in the opposite direction, that is to the right as viewed in FIG, 4. As the piston 74 reverses direction during the remainder of the opening movement of the door in the reverse direction under emergency conditions, the fluid within the chamber end 158 is discharged through the passage 162 to the reservoir. Since the pressure in conduit 72 is at atmospheric level, the spring biased plunger 222 is at its upper position so that such hydraulic fluid being discharged from chamber end 158 will seat the ball valve 224 against its seat 226 and the restriction 230 is effective to establish a pressure in chamber end 158 resisting the manual force applied to the door during emergency operiing.

As the door closes after emergency opening in the reverse direction, the piston 74 will move to the left as viewed in FIG. 4, and the checking piston 194 is positioned so as to trap fluid in chamber end 156 from direct communication to check chamber 148. Accordingly, the adjutable restriction 198 limits the initial closing speed of the door under the bias of the spring subassembly 14.

After the door is closed from its emergency position to a point where the overcenter position of the pivots of drive link 138 and the axis of spindle 36 is reached, the piston 74 begins to move to the right as viewed in FIG. 4. Since the solenoid 68 is not energized, reservoir pressure exists in conduit 72, and the spring biased piston 222 for ball valve 224 is in its upward or inactive position where it does not interfere with the seating of ball 224 against seat 226 to prevent passage of fluid therethrough. Thus, the fluid being discharged from power piston chamber end 158 to the reservoir 54 through conduit 162, 164 seats the ball valve 224 against its seat 226 and the restriction 230 creates a back pressure in chamber end 158 to resist the closing of the door until the door reaches its fully closed position.

From the foregoing, it will be readily apparent that this invention provides a hydraulic operator which is low in cost, flexible in operation and has a unique hydraulic circuit for controlled door opening and closing operation during both automatic and manual operation as well as during emergency breakout in the reverse direction of opening. It is further apparent that the provision of self-adjusting checking pistons further contributes to the low cost of manufacture of the operator.

As will be apparent to persons skilled in the art, various modifications, adaptations and variations of the foregoing specific disclosure can be made without departing from the teachings of the present invention.

What is claimed is:

1. A hydraulically powered operator suited for controlled powered and manual actuation of a door which opens from the door closed position comprising a hydraulic cylinder having a piston defining first and second closed chambers on opposite sides of the piston, a source of presurized hydraulic fluid, a fluid reservoir, first passage means including a valve selectively interconnecting the first chamber to said source and said reservoir, second passage means interconnecting said reservoir and the second chamber, imeans for maintaining both chambers full of hydraulic fluid, means including a one-way valve and a restricted bypass connected in parallel therewith to restrict the rate of flow of fluid from said second chamber to said reservoir as the piston moves in the direction of said second chamber during the manual opening of said door when pressurized fluid is not present in said first closed chamber of said hydraulic cylinder, a third passage interconnecting said first and second passages, and a spring biased valve actuator only in said third passage, said actuator actuating said one-way valve when said source of pressurized fluid is connected to said first chamber to hold said one-way valve open for the unrestricted flow of fluid from said second chamber to said reservoir when said first chamber is connected to said source.

l l f= k l= 

1. A hydraulically powered operator suited for controlled powered and manual actuation of a door which opens from the door closed position comprising a hydraulic cylinder having a piston defining first and second closed chambers on opposite sides of the piston, a source of pressurized hydraulic fluid, a fluid reservoir, first passage means including a valve selectively interconnecting the first chamber to said source and said reservoir, second passage means interconnecting said reservoir and the second chamber, means for maintaining both chambers full of hydraulic fluid, means including a one-way valve and a restricted bypass connected in parallel therewith to restrict the rate of flow of fluid from said second chamber to said reservoir as the piston moves in the direction of said second chamber during the manual opening of said door when pressurized fluid is not present in said first closed chamber of said hydraulic cylinder, a third passage interconnecting said first and second passages, and a spring biased valve actuator only in said third passage, said actuator actuating said one-way valve when said source of pressurized fluid is connected to said first chamber to hold said one-way valve open for the unrestricted flow of fluid from said second chamber to said reservoir when said first chamber is connected to said source. 